Shi'ite Houthi rebels carry a wounded man at the scene of a suicide attack in Sanaa October 9, 2014.

At least 20 people were killed on Thursday in a suicide attack apparently targeting a Shi'ite Muslim Houthi checkpoint in the center of the Yemeni capital Sanaa, witnesses including a Reuters reporter said.

One witness counted at least 20 bodies after the bombing in Tahrir Square in central Sanaa, which is under control of Muslim Shi'ite Houthi. Many other people were wounded in the attack, other witnesses said.

A policemen guarding a local bank near the scene said a man apparently wearing a suicide belt approached the Houthi checkpoint. "He then exploded amidst the (Houthi) security and ordinary people near by," the policemen told Reuters.

No one has claimed responsibility for the attack, but the incident appears to mirror previous bombings carried out by Al Qaeda in the Arabian Peninsula (AQAP).